// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_AURA_CLIENT_WINDOW_STACKING_CLIENT_H_
#define UI_AURA_CLIENT_WINDOW_STACKING_CLIENT_H_

#include "base/memory/scoped_ptr.h"
#include "ui/aura/aura_export.h"
#include "ui/aura/window.h"

namespace aura {
namespace client {

    class AURA_EXPORT WindowStackingClient {
    public:
        // Invoked from the various Window stacking functions. Allows the
        // WindowStackingClient to alter the source, target and/or direction to stack.
        // Returns true if stacking should continue; false if the stacking should not
        // happen.
        virtual bool AdjustStacking(Window** child,
            Window** target,
            Window::StackDirection* direction)
            = 0;

    protected:
        virtual ~WindowStackingClient() { }
    };

    // Sets/gets the WindowStackingClient. This does *not* take ownership of
    // |client|. It is assumed the caller will invoke SetWindowStackingClient(NULL)
    // before deleting |client|.
    AURA_EXPORT void SetWindowStackingClient(WindowStackingClient* client);
    AURA_EXPORT WindowStackingClient* GetWindowStackingClient();

} // namespace client
} // namespace aura

#endif // UI_AURA_CLIENT_WINDOW_STACKING_CLIENT_H_
